Heated solid electrolyte oxygen sensor

Abstract

A self heating, readily assembleable solid electrolyte oxygen sensor is provided. A heater subassembly readily adaptable to unheated oxygen sensor technology, provides the means for positioning and rigidly securing the heater element within the oxygen sensing device through the use of locating means on the heater element and corresponding locating projections on the electric connector terminals. The terminals also provide the means for electrically coupling the resistance heating wires of the heater element to the external ground and power signals.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. An oxygen sensing device, comprising: a substantially tubular solid electrolyte body having an elongated bore axially located, with a first end closed by said solid electrolyte and a second end open, said solid electrolyte body having a reference electrode provided on an inner surface thereof and a measuring electrode provided on an outer surface thereof; a housing, said housing supports said solid electrolyte body so that said measuring electrode of said solid electrolyte body contacts the external gas to be measured and so that said reference electrode of said solid electrolyte body is gas tight to the external gas to be measured;   an elongated heater element comprising a heating resistor having a positive coefficient of resistance and a first end inserted within said elongated bore of said solid electrolyte body;   said heater element having holes adjacent a second end, and having means for electric contact to said heating resistor; and   a plurality of electrical connection terminals each having a connecting end for electrical connection to an external signal, a contact end for electrically contacting said means for electric contact to the resistor, and a male portion extending into one of said holes in said heater element to rigidly secure said heater and to prevent rotational movement of the heater element.   
     
     
       2. A device as set forth in claim 1 further comprising an electrically insulative adapter having a generally tubular shape positioned to enclose said electrical connection terminals.